Concrete World (チーズ工場, Chīzu Kōjō, Cheese Factory) is an area accessible from the old Museum.
The basic landscape of this area is comprised of orange/yellow blocks and grey concrete floor tiles with a few scattered pipes sticking out of the ground.
From the Museum's entrance, you can use the elevator on the left to get to the ground floor and explore the area.
Along the top wall of the area is a doorway that will take you up a large tower structure made of the same orange blocks with many elevators leading to different parts of the tower. This area originally housed many things that can now be found in Flying Fish World, which replaced it in later versions. The elevators still work, but many of the places and rooms they lead to are now empty or nonfunctional. The only thing to note is a strange laughing tree at the far right of the roof accessible from the elevators.
Slightly east-southeast of the museum entrance is another doorway, leading to a large looping area known as Concrete World B. Here you can use the Fairy effect to make diamonds appear. The one that is flashing will take you back to the main area.
- Concrete World was originally the main place where you could find Smile-San and the Spacesuit effect in previous versions of the game. Now this (and all its other previous features) have been moved to Flying Fish World. You can still travel up the elevators, but doorways that lead to particular places no longer work.
- It's important to note that BGM 055 can only be fully unlocked if you enter the elevator portions of Concrete World A.
- The map containing the elevator portion of Concrete World A is the largest single map in the entire game.